A doubling in zinc prices since late 2015 and strong outlook for the commodity has fueled a flurry of zinc miner listings on the Toronto Stock Exchange as companies cash in on investor demand for producers of the metal.

Brazil-based Nexa Resources, a top five global zinc producer, is seeking to raise up to $651 million in an initial public offering in Toronto and New York in what would be the world’s biggest zinc-focused IPO since China’s Western Mining Co Ltd in 2007, according to Thomson Reuters data. At least three other zinc miners, including Titan Mining and Dublin-based Group Eleven Resources Corp, are planning listings on the Toronto Stock Exchange or the TSX Venture Exchange (TSX-V) market for small start-ups, according to company filings.